Cracking the Axis: How Codebreaking Intelligence Spurred the Allied Victory in World War II
Dr. Jaclyn Stanke
When students study works about the Allied victory in World War II, they often read about the triumph of superior resources of men and materiel, the famous battles, and the generals that fought them. Rarely do they hear about the role that code breaking intelligence played in the victory. The main reason is that, until recently, most of the information about wartime intelligence achievements remained classified. Since its declassification, memoirists and scholars have published many works to answer questions such as: what were these codes? how were they broken? and most importantly, what effect did the intelligence gained from these codes have on the Allied victory? This paper explores these questions with the ultimate argument that intelligence gained from code breaking had a marked effect in producing victory for the Allies. Indeed, without intelligence, Admiral Chester Nimitz never would have won the Battle of Midway.
The discussion begins with the intelligence failure at Pearl Harbor in 1941. There, US military forces had enough intelligence on hand to lessen or even prevent the disaster of that December. The debacle at Pearl Harbor revealed important dynamics about intelligence gathering and application. Cryptanalyst William Friedman developed a “cryptologic coin” metaphor to explain this dynamic. On one side of the coin was communications intelligence (COMINT) which dealt with gathering intelligence, while the obverse side of the coin was communications security (COMSEC) which dealt with delivering intelligence to commanders in the field of battle. Friedman argued that intelligence could only be used effectively if COMINT and COMSEC were both employed. Thus, it was a failure of COMSEC which led to the disaster at Pearl Harbor. Using this approach to war time intelligence, “Cracking the Axis” traces the development of code breaking throughout the war and argues that once properly applied, intelligence played a significant role in not only winning major climaxes and turning points, but also planning major offensives.
Properly employed intelligence methods played a role in the battles of El-Alamein, Hollandia Landing, Kursk, the strategic landing at Normandy, and the deployment of the Atomic Bomb. However, as this paper argues, perhaps the most crucial moment for code breaking intelligence in World War II was the Battle of Midway. After Pearl Harbor, US intelligence services learned the dynamics of Friedman’s “cryptologic coin” from their British counterparts and set up a code breaking station in Hawaii. It was from this code breaking station that Admiral Nimitz was informed of the Japanese plan to invade the Hawaiian island chain. Due to this information, Admiral Nimitz was able to consolidate his forces and stage one of the most heroic victories in American military history.
